2 * Copyright (C) 2016 Maxime Ripard
3 * Maxime Ripard <maxime.ripard@free-electrons.com>
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation; either version 2 of
8 * the License, or (at your option) any later version.
11 #include <linux/clk-provider.h>
17 unsigned long n, min_n, max_n;
18 unsigned long k, min_k, max_k;
19 unsigned long m, min_m, max_m;
22 static void ccu_nkm_find_best(unsigned long parent, unsigned long rate,
25 unsigned long best_rate = 0;
26 unsigned long best_n = 0, best_k = 0, best_m = 0;
27 unsigned long _n, _k, _m;
29 for (_k = nkm->min_k; _k <= nkm->max_k; _k++) {
30 for (_n = nkm->min_n; _n <= nkm->max_n; _n++) {
31 for (_m = nkm->min_m; _m <= nkm->max_m; _m++) {
32 unsigned long tmp_rate;
34 tmp_rate = parent * _n * _k / _m;
38 if ((rate - tmp_rate) < (rate - best_rate)) {
53 static void ccu_nkm_disable(struct clk_hw *hw)
55 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
57 return ccu_gate_helper_disable(&nkm->common, nkm->enable);
60 static int ccu_nkm_enable(struct clk_hw *hw)
62 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
64 return ccu_gate_helper_enable(&nkm->common, nkm->enable);
67 static int ccu_nkm_is_enabled(struct clk_hw *hw)
69 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
71 return ccu_gate_helper_is_enabled(&nkm->common, nkm->enable);
74 static unsigned long ccu_nkm_recalc_rate(struct clk_hw *hw,
75 unsigned long parent_rate)
77 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
78 unsigned long n, m, k;
81 reg = readl(nkm->common.base + nkm->common.reg);
83 n = reg >> nkm->n.shift;
84 n &= (1 << nkm->n.width) - 1;
89 k = reg >> nkm->k.shift;
90 k &= (1 << nkm->k.width) - 1;
95 m = reg >> nkm->m.shift;
96 m &= (1 << nkm->m.width) - 1;
101 return parent_rate * n * k / m;
104 static unsigned long ccu_nkm_round_rate(struct ccu_mux_internal *mux,
105 unsigned long parent_rate,
109 struct ccu_nkm *nkm = data;
110 struct _ccu_nkm _nkm;
112 _nkm.min_n = nkm->n.min;
113 _nkm.max_n = nkm->n.max ?: 1 << nkm->n.width;
114 _nkm.min_k = nkm->k.min;
115 _nkm.max_k = nkm->k.max ?: 1 << nkm->k.width;
117 _nkm.max_m = nkm->m.max ?: 1 << nkm->m.width;
119 ccu_nkm_find_best(parent_rate, rate, &_nkm);
121 return parent_rate * _nkm.n * _nkm.k / _nkm.m;
124 static int ccu_nkm_determine_rate(struct clk_hw *hw,
125 struct clk_rate_request *req)
127 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
129 return ccu_mux_helper_determine_rate(&nkm->common, &nkm->mux,
130 req, ccu_nkm_round_rate, nkm);
133 static int ccu_nkm_set_rate(struct clk_hw *hw, unsigned long rate,
134 unsigned long parent_rate)
136 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
137 struct _ccu_nkm _nkm;
141 _nkm.min_n = nkm->n.min;
142 _nkm.max_n = nkm->n.max ?: 1 << nkm->n.width;
143 _nkm.min_k = nkm->k.min;
144 _nkm.max_k = nkm->k.max ?: 1 << nkm->k.width;
146 _nkm.max_m = nkm->m.max ?: 1 << nkm->m.width;
148 ccu_nkm_find_best(parent_rate, rate, &_nkm);
150 spin_lock_irqsave(nkm->common.lock, flags);
152 reg = readl(nkm->common.base + nkm->common.reg);
153 reg &= ~GENMASK(nkm->n.width + nkm->n.shift - 1, nkm->n.shift);
154 reg &= ~GENMASK(nkm->k.width + nkm->k.shift - 1, nkm->k.shift);
155 reg &= ~GENMASK(nkm->m.width + nkm->m.shift - 1, nkm->m.shift);
157 reg |= (_nkm.n - nkm->n.offset) << nkm->n.shift;
158 reg |= (_nkm.k - nkm->k.offset) << nkm->k.shift;
159 reg |= (_nkm.m - nkm->m.offset) << nkm->m.shift;
160 writel(reg, nkm->common.base + nkm->common.reg);
162 spin_unlock_irqrestore(nkm->common.lock, flags);
164 ccu_helper_wait_for_lock(&nkm->common, nkm->lock);
169 static u8 ccu_nkm_get_parent(struct clk_hw *hw)
171 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
173 return ccu_mux_helper_get_parent(&nkm->common, &nkm->mux);
176 static int ccu_nkm_set_parent(struct clk_hw *hw, u8 index)
178 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
180 return ccu_mux_helper_set_parent(&nkm->common, &nkm->mux, index);
183 const struct clk_ops ccu_nkm_ops = {
184 .disable = ccu_nkm_disable,
185 .enable = ccu_nkm_enable,
186 .is_enabled = ccu_nkm_is_enabled,
188 .get_parent = ccu_nkm_get_parent,
189 .set_parent = ccu_nkm_set_parent,
191 .determine_rate = ccu_nkm_determine_rate,
192 .recalc_rate = ccu_nkm_recalc_rate,
193 .set_rate = ccu_nkm_set_rate,